BACKGROUND Mitotic inhibitors have been successful in cancer therapy. BI-2536 is a recently develop inhibitor of the mitotic kinase PLK1. It potently inhibits the growth of a range of cancer cell lines. PURPOSE To test the sensitivity of a panel of multiple myeloma cell lines to the PLK1 inhibitor and to study the underlying genetic causes of this sensitivity. SIGNIFICANT MATERIALS AND METHODS A panel of multiple myeloma cell lines. FY2010 ACCOMPLISHMENT We have measured the IC50 values of the PLK1 inhibitor BI-2536 in 20 multiple myeloma cell lines.